fix: cache registry promise and cap stderr buffer

- Cache the Promise instead of the resolved PluginRegistry to prevent
  concurrent callers from racing past the null check and creating
  multiple registries before loadFromConfig completes.
- Cap stderrChunks to 100 entries since only early startup errors
  (stale build detection) are checked — unbounded growth wastes memory
  for long-running dashboard processes.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/cli/src/commands/dashboard.ts

@@ -69,9 +69,13 @@ export function registerDashboard(program: Command): void {
 
       const stderrChunks: string[] = [];
 
+      const MAX_STDERR_CHUNKS = 100;
+
       child.stderr?.on("data", (data: Buffer) => {
         const text = data.toString();
-        stderrChunks.push(text);
+        if (stderrChunks.length < MAX_STDERR_CHUNKS) {
+          stderrChunks.push(text);
+        }
         // Still show stderr to the user
         process.stderr.write(data);
       });

packages/cli/src/lib/create-session-manager.ts

@@ -15,18 +15,22 @@ import {
   type PluginRegistry,
 } from "@composio/ao-core";
 
-let cachedRegistry: PluginRegistry | null = null;
+let registryPromise: Promise<PluginRegistry> | null = null;
 
 /**
  * Get or create the plugin registry.
- * Cached to avoid re-importing all plugins on every call.
+ * Caches the Promise (not the resolved value) so concurrent callers
+ * await the same initialization rather than racing.
  */
 async function getRegistry(config: OrchestratorConfig): Promise<PluginRegistry> {
-  if (!cachedRegistry) {
-    cachedRegistry = createPluginRegistry();
-    await cachedRegistry.loadFromConfig(config);
+  if (!registryPromise) {
+    registryPromise = (async () => {
+      const registry = createPluginRegistry();
+      await registry.loadFromConfig(config);
+      return registry;
+    })();
   }
-  return cachedRegistry;
+  return registryPromise;
 }
 
 /**